caca-config: command not found

Have You tried accessing the binary with the full path?

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On CentOS possible default full paths are:

/usr/bin/caca-config - from package: libcaca-devel

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/bin/caca-config - from package: libcaca-dev

You may install the required package with command apt-get install {package}
Error in other languages:
caca-config: bevel nie gevind nie
caca-config: comandă negăsită
caca-config: comando não encontrado
caca-config: commande introuvable
caca-config: command not found
caca-config: käsku ei ole
caca-config: không tìm thấy lệnh
caca-config: komanda nerasta
caca-config: Kommando nicht gefunden.
caca-config: kommandot finns inte
caca-config: komut yok
caca-config: nie znaleziono polecenia
caca-config: níor aimsíodh an t-ordú
caca-config: no se encontró la orden
caca-config: no s'ha trobat l'ordre
caca-config: opdracht niet gevonden
caca-config: parancs nem található
caca-config: perintah tidak ditemukan
caca-config: príkaz nenájdený
caca-config: příkaz nenalezen
caca-config: команда не найдена
caca-config: командата не е открита
caca-config: 命令找不到
caca-config: コマンドが見つかりません